Freon operated, hermetically sealed compressors for use in domestic refrigerators are known and mainly comprise a casing containing an electric motor that drives by means of a camshaft a piston located inside a cylinder block. The working fluid is supplied through a suction pipe penetrating into a body that supports the entire assembly. Lubrication is achieved by a pump provided with a driving shaft, while the assembly within the casing is suspended from a plurality of springs, radially or perpendicularly disposed in relation to a horizontal plane, and attached to a plurality of ears secured to the casing and to the assembly. Electrical power is supplied through a triple pole terminal located close to the suction pipe through which the working fluid is circulated.
The main disadvantage of such compressors lies in an increased overall size of the casing since, for attaching the suspension springs of the compressor assembly, it is imperative that a plurality of inside ears be used. A further disadvantage is that the suction inlet is arranged opposite the suction pipe permitting some heating of the cooled working fluid that implicity results in a diminished volumetric efficiency of the compressor.
A further disadvantage is to be attributed to the oil pump and to its blade being press-fitted, so that the unit may have a comparatively lower pumping efficiency; in some cases it is possible for these parts to detach from one another, bringing about interruptions in operation.
Still a further disadvantage is the relatively high noise and vibration levels that can be attributed to the components supplying by suction the working fluid to the cylinder block to their suspension system, to the large clearances between adjacent component parts as well as to the comparatively high mass of the latter.